Certainly Mango represents a substantial revamp of Microsoft's mobile platform, which is struggling for adoption in the face of competition from Google Android and Apple's iPhone. In contrast to those platforms, which offer gridlike screens of individual apps, Windows Phone consolidates Web content and applications into a set of subject-specific Hubs, including "Office" and "People."

As Microsoft executives demonstrated for a small group of media and analysts during a May 24 press event in New York City, the new features include a redesigned Xbox Live Hub, home-screen tiles capable of displaying up-to-the-minute information such as instant messages and social-networking data, the ability to consolidate friends and colleagues into groups, and visual voicemail. All in all, Microsoft is planning to add some 500 new elements to Windows Phone.

Mango will be released sometime this fall. That's some distance away for a company wrestling to hold onto its market share. Although research firm Gartner estimated that Windows Phone sold 1.6 million units in the first quarter of 2011, recent data from comScore suggests that Microsoft's share of the overall smartphone market continues to erode--a situation probably not helped by some well-publicized snafus with the first two Windows Phone software updates.

Even if the pre-Mango Windows Phone continues a slide in market share, Microsoft has managed to secure some long-term commitments from its manufacturing partners.

"We have some Windows Mango phones," HTC CEO Peter Chou reportedly told Reuters May 25. "We are very committed to Windows phone products." However, he offered no guidance on when those new devices might appear.

Analysts generally view Microsoft's deal with Nokia, which will see Windows Phone ported onto the latter's smartphones, as a chance for the Windows Phone platform to gain some additional momentum--at least overseas, where Nokia continues to maintain a strong presence despite challenges from Android and iOS.